The present invention relates generally to a unique and novel keyless entry system for operating automotive devices, such as door locks, a trunk lid lock, a glove box lid lock, steering lock devices and/or a starter motor without mechanical keys. More specifically, the invention relates to a keyless entry system which comprises a wireless transmitter transmitting a preset code to a controller which actuates the automotive devices when the code from the transmitter matches a preset code stored in the controller. Additionally, the invention relates to an alarm or cautioning means associated with the keyless entry system for producing an alarm or a caution when a user leaves the transmitter in the passenger compartment and starts to leave the vehicle.
U.S. Pat. No. 4,205,325, to Haygood et al, discloses a keyless entry system for an automotive vehicle permitting a plurality of operations to be achieved from outside the vehicle by one who is knowledgeable of predetermined digital codes. Functions such as unlocking the doors of the vehicle, opening the rear trunk lid, opening a roof window, lowering the windows or programming the system with a user-preferred digital access code can all be performed by proper sequential operation of a digital keyboard mounted on the outside of the vehicle.
This and other conventional keyless entry systems require the user to accurately input the predetermined code through the keybord. Although such keyless entry systems have been well developed and considered useful for eliminating the need for mechanical keys, a serious problem may occur when the user of the vehicle forgets the predetermined code. If the user is outside of the vehicle and the vehicle door lock device is holding the doors locked, the user cannot unlock the door locks until he remembers the predetermined code.
The present invention provides a novel and more useful system for operating the vehicle devices without an ignition key and without requiring manual entry of a predetermined code.